ASME-Landmark:Mount Washington Cog Railway


Mount Washington, rising 6,288 feet above sea level in the mountainous north country of New Hampshire, is the highest peak in the Northeast. The world's first cog railway ascends almost 3,600 feet along a western spur of the mountain between Burt and Ammonoosuc Ravines from the Marshfield Base Station.

Inspired by his own difficulty ascending the peak of Mt. Washington, civil-mechanical engineer Sylvester Marsh applied to the New Hampshire Legislature for a charter to construct a steam railway to the summit. In 1861, Marsh patented the now famous cog mechanism, a device for making the locomotive safe either ascending or descending a grade, which drove toothed wheels into a ladder-like between-rails rack bolted to the cross ties of a three-mile trestle. Marsh also developed a ratchet safety cog with gear reduction and a breaking mechanism.

The first specialty built steam locomotive designed by Marsh was Locomotive No. 1, "Hero," popularly known as Peppersass, with one pair of cylinders that powered only the front axle through gears. The vertical boiler, rumored to have been previously used by a sawmill, was hung on trunnions so that it would remain upright as the locomotive overcame steep grades.

The first trip on the railway was made on August 29, 1866. On July 3, 1869, the first train reached the summit of Mt. Washington and the Cog Railway became the first mountain climbing railway in the world, with an average grade of 25%, and a 37.4% grade at Jacob's Ladder. It has been in continuous operation since its 1869 opening except for one year during World War I and three years during World War II.

A victim of a 1929 accident, Peppersass was re-assembled and is now on display at the Marshfield Base Station. See ASME website for more information